G8AGN's Laser transmitter as used by G3PHO
Peter, PHO, and I had a 1 way test over a 6.7 km path last night on the west side of Sheffield. The gear used was my Tx and Rx but now engineered properly (no duct tape!). The TX now has a G0MRF driver circuit and can accomodate a G4FRE CW ident keyer. No beam expander was used but might be incorporated later.
TX Setup. Note the IC 202 SSB talkback and sturdy tripod
The Rx still uses the original G0MRF circuit (OPT210 with 2M resistor) but I may build a 0MRF Mk2 for comparison. The two ends of the path were on opposite sides of a valley and as it was dark when we set up, Peter (with the TX) set up the laser by sighting on my car headlights. Needless to say, I didn't need any aids to see the laser which was incredibly bright and even more impressive in appearance than when viewed during our previous 600m test. We are starting to appreciate the need for very fine pointing accuracy on the laser. Peter is now intending to build up his own system, so we hope to do some 2 way tests later in the year .
Updated 17 Sept 2004